get.parms <- function(data) {
  # Convertir a porcentajes
  perc <- apply(data, 2, function(x) x/rowSums(data))
  mean <- apply(perc, 2 , mean)
  # Log-ratios
  log.ratios <- log(perc[,-ncol(perc)]/perc[,ncol(perc)])
  # Parametros
  mu <- apply(log.ratios, 2, mean)
  sigma <- cov(log.ratios)
  # Return
  return(list(n=nrow(data), mean=mean, mu=mu, sigma=sigma))
}
